Derivatives and Hedging Activities (Derivatives in Statement of Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Derivative Instruments, Gain (Loss) [Line Items]
Advances	$ 473	$ 759
AFS securities	268	283
Bonds	(594)	(850)
Discount notes	(126)	(193)
Net gain/(loss) on derivatives	(15)	15
Advances \| Interest Income \| Interest Rate Contract
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	(64)	311
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	102	(153)
Net Gains Losses On Qualifying Active Fair Value Hedging Relationships	38	158
Available-for-sale Securities \| Interest Income \| Interest Rate Contract
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	(218)	398
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	275	(294)
Net Gains Losses On Qualifying Active Fair Value Hedging Relationships	57	104
Consolidated Obligations, Bonds \| Interest Expense \| Interest Rate Contract
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	44	(161)
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	(100)	22
Net Gains Losses On Qualifying Active Fair Value Hedging Relationships	(56)	$ (139)
Discount notes \| Interest Expense \| Interest Rate Contract
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	(2)
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	4
Net Gains Losses On Qualifying Active Fair Value Hedging Relationships	$ 2

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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